if you have a simple form with out any controls on it then the glass panel is working ok.if you for example add a datagridview in the form and then try to add the glass panel above form and datagridview , the glass effect will affect only the empty area of the form and will not affect the datagridview

Heres a C# solution that will fit into a single file and is easy to implement in any project.

By default the advanced graphic options are turned off and can be turned on using properties in the "Glass" section.I also included a few code optimizations and disposed properly of certain objects within the paint methods, also included double buffering on the control